How can I texture individual tiles?
if you have some image editor like Gimp or Photoshop you can create the composition with the diferent textures.



1.- Unwarp the rectangle
2.- export the Uv Layout


  Than create your composition in Gimp or Photoshop, with the exported UV-Layout
  3.- In Cycles, create a Material
  4.- and add the Image Texture Nodes with your composition image.